Non-aqueous lithium electrochemical cells typically include an anode, a lithium electrolyte prepared from a lithium salt dissolved in one or more organic solvents and a cathode of an electrochemically active material, typically a chalcogenide of a transition metal. During discharge, lithium ions from the anode pass through the liquid electrolyte to the electrochemically active material of the cathode where the ions are taken up with the simultaneous release of electrical energy. During charging, the flow of ions is reversed so that lithium ions pass from the electrochemically active cathode material through the electrolyte and are plated back onto the lithium anode.
Recently, the lithium metal anode has been replaced with a carbon anode such as coke or graphite intercalated with lithium ions to form Li.sub.x C. In operation of the cell, lithium passes from the carbon through the electrolyte to the cathode where it is taken up just as in a cell with a metallic lithium anode. During recharge, the lithium is transferred back to the anode where it reintercalates into the carbon. Because no metallic lithium is present in the cell, melting of the anode does not occur even under abuse conditions. Also, because lithium is reincorporated into the anode by intercalation rather than by plating, dendritic and spongy lithium growth does not occur. Non-aqueous lithium electrochemical cells are discussed in U.S. Pat. Nos. 4,472,487, 4,668,595 and 5,028,500.
Current collectors are used with carbon anodes and cathodes as described, for example, in U.S. Pat. Nos. 4,925,752, 5,011,501 and 5,326,653. In fabricating cathodes for instance, a cathode material comprising solvent(s), polymer, and electrochemically active particulate material is laminated onto a current collector. Thereafter, the solvent(s) are allowed to evaporate to form a sheet of cathode material on the current collector. Unfortunately, prior art anode and cathode materials often do not adhere adequately to the surface of the current collector which reduces the performance of the electrochemical cell. Furthermore, prior art current collector tabs often do not provide adequate electrical contact between the current collector and the external load.